Frequencies for first 10,000 rows of injuryoflg variable in natl1975 dataset :

      Birth |
   Injuries |
 (by State) |
  flag (Not |
      1972) |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |     10,000      100.00      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 3 Jan 2016